1、廠房多點位移計安裝措施1、工程概況上塔馬克西水電工程（UTKHEP）位于Dolakha地區(qū)的塔馬克西河上，地 下廠房位于gongar村。地下廠房全長141.62m,最大寬度14.9m,廠房最低點 高程為1158.70,頂拱中心高程為1188.30。廠房多點位移計用于測量廠房周邊 巖石由于爆破造成的位移形變，及廠房周邊巖壁永久平安監(jiān)測。2、廠房地質(zhì)情況概述廠房巖石為深灰色片麻巖，片麻理結(jié)構(gòu)，無風化，整體圍巖較完整，局部拱 肩部位圍巖較破碎，形成碎塊。局部有地下水發(fā)育，水量較小，廠房圍巖整體較 為完整，穩(wěn)定性較好。3、多點位移計布置情況廠房部位按照原招標文件要求，在主交通洞布置3支多點位移計、廠房

2、周邊 隧洞布置6支多點位移計、廠房及主變洞布置5支多點位移計，我方于4月接到 現(xiàn)場工程師指令，要求在廠房布置總共24支、孔深20m的4個位移傳感器的多 點位移計，于7月26日接到正式的儀器布置圖，由于傳感器的增加以及孔深及 數(shù)量的增加，多點位移計的安裝施工導致廠房的開挖施工受到嚴重的干擾。廠房 總體開挖施工工期將延后123天。詳見多點位移計工期安排說明。廠房多點位移計總計安裝24支，分布在頂拱、邊墻及南北兩側(cè)端墻。每支 位移計設置4個測點，分別距離孔口 5m、10m、15m、20mo測點分布表表1編號部位（樁號）高程角度（與水平面夾角）備注1北端墻1175.300廠房中心線2南端墻1175.3

3、00廠房中心線3南端墻1165.300機組中心線40+0331188.4090廠房中心線51185.3045頂拱右側(cè)61185.30-45頂拱左側(cè)71176.3015右邊墻The Method Statement of Multipoint Borehole ExtensometerInstallation for Powerhouse.General DescriptionUpper Tamakoshi Hydroelectric Project is located on the Tamakoshi river within Dolakha area. And the undergroun

4、d powerhouse is located near the Gongar village. The total length of the powerhouse is 141.62m, and the elevation of the lowest point of the powerhouse is 1158.70m, and the elevation of the center point in its crown is 1188.30m. The multipoint extensometer is used for measuring and monitoring the ro

5、ck deformation and displacement due to blasting around powerhouse.General Description for the Geological Condition Within the PowerhouseRocks in the powerhouse are dark-grey gnesis, gneissic schistosity, no weathering and slightly fractured rock next to the crown. Underground water exists with a min

6、or quantity within the area. All in all, the surrounding rock in the powerhouse in general is good and stabilized.Layout of the Multipoint Borehole ExtensometerIn accordance with the requirements of tendering document, there are three extensometers shall be installed in main access tunnel, six in th

7、e access tunnels around powerhouse, five in powerhouse cavern and transformer cavern. The site instruction received in April this year has indicated that totally twenty-four extensometers shall be installed and the depth of holes shall be 20m. The official layout of multipoint borehole extensometer

8、was received on July 26, 2012. Due to the increasing quantity of sensors as well as holes, and also due to the depth of the holes increased, the site construction in powerhouse, to some degree, was interfered by the installation of multipoint borehole extensometer.There are 24 extensometers in total

9、 installed at the crown, side walls, north and south gable wall of the powerhouse cavern. Each of the extensometers has four measuringpoints, and the distances from each of the points to the entrance of a hole accordingly are 5m, 10m, 15m and 20m.S/NcationLo (chainage)ElevationangleRemarks1North gab

10、le wall1175.300Center line of powerhouse2South gable wall1175.300Center line of powerhouse3South gable wall1165.300Center line of units40+0331188.4090Center line of powerhouse51185.3045Left side of crown61185.30-45Left side of crown71176.3015Right side wall81176.30-10Leftt side wall91169.3015Right s

11、ide wall101168.30-15Leftt side wall110+0601188.4090Center line of powerhouse121185.3045Right side of crown131185.30-45Left side of crown141176.3015Right side wall151176.30-10Leftt side wall161169.3015Right side wall171168.30-15Leftt side wall180+1201188.4090Center line of powerhouse191185.3045Right

12、side of crown201185.30-45Left side of crown211176.3015Right side wall221176.30-10Leftt side wall231169.3015Right side wall241168.30-15Leftt side wallTable of Measuring PointsTable 1Layout of Measuring Points (Table 1)v1176. 30v1176. 301173. 50vS-FACE。N-FACE1176. 30V1168. 301169. 30V1165. 30V oS-FACE

13、The Installation and Construction Schedule of Multipoint Borehole ExtensometerAccording to the instruction of installation from the manufacturer, the installation should be under the guidance of technical people. And the engineer shall be informed time to time about some problems arising from the in

14、stallation.Comparing the site instruction issued by the Engineer with the relevant requirements in the contract, in the site instruction, the depth of holes and quantity of measuring points are increased, and the diameter of holes is enlarged as well. Therefore, the construction becomes more difficu

15、lt and the time for completion also have to be extended. So 6 days have to be spent on the installation of each extensometer, namely, 4 days for hole drilling and 2days for installation and inspection.Preparation before ConstructionCalibrating and checking the performance of the extensometer.Surveyi

16、ng and setting out for all the locations of holes, marking them with paint and recording all the locations as well.Visiting the construction site regularly and as per the construction schedule delivering the needed equipment to the site with careful handling.Drilling and Construction ScheduleDrillin

17、g RequirementsAccording to the design(there should be 4 measuring points in each of the hole), QZJ100B borehole drill shall be adopted for the construction. The diameter of the hole for extensometer shall be 0 110mm, and then the Im section (from the entrance to the inside of the hole), shall be enl

18、arged into 150mm in the direction of the same axis. Drilling shall be completely carried out according to the approved location, depth and angle by the Engineer and make sure the depth of the hole shall be Im more than the depth of the deepest measuring point. The deviation of the location should no

19、t excess 20cm. After drilling completed, the hole should be washed with water, inspected and measured in terms of depth, location and angle. Then all the completed holes shall be inspected and accepted by the engineer, thereafter installation can be started.The Construction ProcedureConstruction for

20、 Extensometer with a Elevation Above 1176.3m.There are totally nine extensometers with a elevation above 1176.3m, all located at the crown section. If these extensometers are installed after PTH excavation completed, then the second bench excavation for powerhouse cavern shall be extended for 54 day

21、s. This delay will negatively affects the whole progress of the project. So our plan is that after the second bench excavation & crane beam excavation completed and concreting there started, then the extensometer construction for the crown shall begin. The elevation of the second bench at the bottom

22、 is 1177.70m, and the maximum distance from the bottom to the crown is 10.7m, so manually scaffold assembling shall be adopted as a platform (7m high) for drilling and installation. The QZJ100B borehole drill shall be lifted up with 16t crane onto the platform, and be fixed there manually, and then

23、construction can be started. On the condition that there should be no any interference with the concreting of the crane beam, the installation of extensometer shall be performed during the period waiting for the target strength. It is expected that the third bench excavation in the powerhouse cavern

24、 will be extended for 39 days. The construction period shall be scheduled from 16th December 2012 to 8th February 2013.Construction for Extensometer with the Scope of Elevation from 1176.3m to 1173.50m at Side Wall and North & South Gable WallThere are totally 8 multipoint extensometers at side wall

25、 (el. 1176.3m) and north&south gable wall(el. 1173.50m) , among them, 6 in side wall, 1 in north gable wall and 1 in south gable wall. After the third bench excavation & support for powerhouse cavern completed, the steel form carrier shall be adopted for the drilling and installation of multipoint b

26、orehole extensometer. The QZJ100B borehole drill shall be lifted up with 16t crane onto the steel form carrier. Therefore, it is expected that the the fourth bench excavation for powerhouse cavern will be extended for 48 days. The construction period shall be scheduled from 26th March 2013 to 12th M

27、ay 2013.Construction for Extensometer with the Scope of Elevation from 1168.3m to 1169.30m at Side WallThere are totally 6 multipoint extensometers both at the elevation 1168.3m and elevation 1169.30m. After the fourth bench excavation & support for powerhouse cavern completed, the steel form carrie

28、r shall be adopted for the drilling and installation of multipoint borehole extensometer. The QZJ100B borehole drill shall be lifted up with 16t crane onto the steel form carrier. Therefore, it is expected that the fifth bench excavation of powerhouse cavern will be extended for 36 days. The constru

29、ction period shall be scheduled from 27th June 2013 to 1st August 2013.Construction for Extensometer with the Elevation 1165.3mThere is only one extensometer at south gable wall( el. 1165.3m ), After the fifth bench excavation & support for powerhouse cavern completed, the steel form carrier shall b

30、e adopted for the drilling and installation of multipoint borehole extensometer. The QZJ100B borehole drill shall be lifted up with 16t crane onto the steel form carrier. The installation of the extensometer shall be carried out as the the sixth bench excavation for powerhouse cavern started. The co

31、nstruction period shall be scheduled from 16th September 2013 to 21st September 2013.Schedule for Excavation of Powerhouse Cavern & Installation of ExtensometerSchedule for Excavation of Powerhouse Cavern & Installation of ExtensometerPrograme of Powerhouse Excavation and Installation of Extensomete

32、rInstallationIn accordance with the instruction from the manufacturer, assembling the anchor head, transmission pipe, protective pipe and sensor, all these shall be performed first. The joint of measuring bar and protective pipe (PVC) should be connected properly and tightly. According to the field

33、condition of installation, the method, assembling around the entrance of hole, shall be adopted for the crown and side wall, and the method, assembling on the ground, shall be applied to the south & north gable wall.As for the assembling around the entrance of hole, it strictly requires that all the

34、 anchor heads and connecting rods, one by one, shall be assembled and labeled for fear of confusion. The measuring bar and base shall be preassembled. Every anchor head shall be tied with safety rope. And grouting pipe shall be fixed tightly to the anchor head. According to the prelabeled sequence,

35、before assembling, all the parts shall be checked and accepted, then just can be put into a hole. When putting into a hole, people should be very careful in case of transmission rod and supporting ring rotating. After all anchor heads and transmission pipe installed and checked without any mistake,

36、sensors shall be fixed with wooden wedges and keep them at the same surface with the hole entrance and then lead cable and vent-pipe out of the hole.GroutingThe grout tube and vent-pipe shall be fixed according to the direction of drilling. Generally, if the hole is upward or diagonally upward, the

37、grout tube should be put into the hole 5m; the vent-pipe should go deep into the hole until its end is near the bottom. And the entrance of the hole shall be plugged and blocked with grout. For a hole which is horizontal, the grout tube shall go deep into the hole until its end is near the bottom an

38、d vent-pipe in this case is no need; the grout tube shall be led out from the space between the mounting base and wall of the hole.When install the extensometer, the load (the weight of the equipment and grouting pressure) for the equipment itself shall be took into consideration. If the rock surfac

39、e around the entrance of the hole is in a good condition, then anchor bolt and steel bar shall be adopted as support; if it is adverse, some special support shall be used for the entrance of the hole until the grout is consolidated, then the special support can be dismantled. As for a hole in the ho

40、rizontal direction, its support structure should keep the outer part of the assembling in immovable condition, and at the same time, it should be avoided that displacement takes place due to the grout sedimentation inside the hole.After consolidation of the grout at the entrance of a hole, if a test

41、 on it is acceptable, the hole entrance shall be blocked with grout. After measuring bar, protective pipe and grout tube installation completed, grouting for the full hole shall be performed, and the water-cement ratio of the grout shall be 1:0.5, and the grouting pressure shall be less than 0.3MPa.

42、 When grouting, displacement of the whole rod and anchor head should be avoided. After fully grouted inside the hole, the hole entrance shall be blocked to wait for grout consolidation. During that time, vibration to the location of the extensometer and interference from people should be prevented,

43、and some people shall be assigned to be in charge of protecting the installed extensometer. After consolidation for 24 hours, the entrance device shall be opened, if a test on the extensometer is acceptable, then the cable inside can be led out, and finally the the entrance device and protective she

44、ll shall be installed.Cabling and ProtectionCablingThe sensor of the extensometer is short lead, according to the field condition, it shall be lengthened to some extent. Before connection of cable, peel the end part of cable for 10cm to expose the core wire. And for the remaining part of the cable s

45、hall be roughened by abrasive paper for about 3cm. The cable coat is 6 12mm to 6 14mm heat-shrinkable tube, and the core wire shall be connected (color should be matched) and welded together. Insufficient welding shall be prevented and welding slag shall be removed. A sufficient length of cable shou

46、ld be remained for convenience of installation. Before installation, cable should be tied into a bundle and put into a temporary junction box, and the wire heads should be coated and protected by insulation tape. After welding core wire completed, a reading device shall be used to measure and test t

47、he installed equipment. And the multimeter shall be used as well to measure the electric resistance value between the core wires of the cable. Short circuit and open circuit in the connecting joints caused by improper welding should be prevented.Protection of CableAfter the cable led out by sensor,

48、in order to prevent the cable from damage caused by blasting, a additional protective pipe shall be applied to protect the exposed part of cable and the remaining part shall be protected by temporary junction box, after the lining construction in the powerhouse cavern completed, cable shall be linke

49、d to a reading equipment in a monitoring room. And the protective pipe of cable shall be buried into concrete for convenience of circuit examination and repairing after the project completed.ReadingMethod of ReadingAfter installation, the signal cable shall be linked to a reading device, BGK-408, wh

50、ose reading shall display frequency module. In accordance with the manual of BGK-408, the relevant data shall be processed accordingly.The data is a relatively variable quantity, therefore, after installation completed, the initial reading shall be taken. Thereafter, a data-processed software shall

51、be adopted for data analysis.Frequency of Readingafter each blast, until the graph show the initial rapid linear convergence phase has passed81176.30-10左邊墻91169.3015右邊墻101168.30-15左邊墻110+0601188.4090廠房中心線121185.3045頂拱右側(cè)131185.30-45頂拱左側(cè)141176.3015右邊墻151176.30-10左邊墻161169.3015右邊墻171168.30-15左邊墻180+120

52、1188.4090廠房中心線191185.3045頂拱右側(cè)201185.30-45頂拱左側(cè)211176.3015右邊墻221176.30-10左邊墻231169.3015右邊墻241168.30-15左邊墻thereafter at two blast intervals until the face has advanced to at least 20 mthereafter at weekly intervals until the readings have stabilised5、Resource Allocation5.1 Description of Material & Equ

53、ipmentTable of Material & Equipment InputS/NDescriptionUnitQtyRemarks1QZJ100B borehole drillset12Injecting pumpset13Loaderset13 m34Steel form carrier for drilling & blastingset15Trailerset1Transportation for material and equipment6Craneset116tTable25.2 Description of ManpowerS/NType of manpowerUnitQ

54、uantityRemarks1FormanNo2Instruction of installation2Driver of loaderNo13DrillerNo34Grouting labourNo35Unskilled labourNo66ElectricianNo17DriverNo28Crane operatorNo1Table of Manpower InputTable 3測點布置圖(圖1)1165. 30v oS-FACE4、多點位移計安裝及施工計劃安排按照廠家安裝手冊要求，在技術(shù)人員的指導下進行多點位移計安裝工作，并 及時向工程師報告安裝中發(fā)生的問題。實際工程師下發(fā)指令與原合同

55、文件規(guī)定的多點位移計安裝要求相比，孔深增 長、測點增加、孔徑增大，因此增大了施工難度，延長施工工期，每支多點位移 計安裝需要6天時間，其中鉆孔需要4天時間，安裝及檢查需要2天時間。施工前準備(1)對多點位移計的性能進行率定和質(zhì)量檢查；(2)進行埋設點的測量放樣，用油漆做好記號，記錄各安裝點的位置；(3)隨時了解工地上的現(xiàn)場施工情況，根據(jù)安裝計劃將埋設部位所須儀器 運輸?shù)浆F(xiàn)場，運輸途中必須輕拿輕放，切忌碰撞儀器。鉆孔及施工計劃安排鉆孔要求按設計要求鉆孔（每孔4個測點），使用QZJ100B潛孔鉆機鉆孔。多點位移 計鉆孔孔徑6110mm,孔口 1m段同軸線擴大至150mm,嚴格按經(jīng)工程師批準的 孔位

56、孔深及角度施鉆，并保證孔深比最深測點深1.0m,鉆孔孔位偏差不大于 20cmo鉆孔結(jié)束后應沖洗干凈，檢查鉆孔通暢情況，測量鉆孔深度、方位、傾 角。鉆孔完成后，經(jīng)工程師檢查合格后進行安裝施工。廠房部位多點位移計施工順序A、高程1176.3m以上多點位移計的施工高程1176.3m以上多點位移計共有9支，均分布于頂拱，如果多點位移計的 鉆孔及安裝施工安排在第一層開挖支護完成后進行，那么需將第二層開挖延后54 天，這對總體的施工進度計劃非常不利，因此我方計劃頂拱的多點位移計施工在 廠房二層及巖錨梁開挖完成后，澆筑碎期間開始開始，廠房二層開挖底高程為 1177.70,與頂拱安裝點最大高差10.7m,所以

57、采用人工搭設腳手架作為鉆孔及安 裝施工平臺，施工平臺高7m。QZJ100B潛孔鉆機采用16t吊車吊至平臺上，人 工固定后開始鉆孔施工。在不影響巖壁吊車梁正常混凝土澆筑的情況下，多點位 移計安裝安排在巖壁吊車梁混凝土待強期開始施工，預計多點位移計安裝將造成 廠房第三層開挖延后39天。施工工期安排為2012年12月16日2013年2月8 日。B、高程1176.3m高程1173.50m邊墻及南北端墻多點位移計的施工高程1176.3m邊墻多點位移計及高程1173.50m南北端墻多點位移計共有8 支，其中邊墻6支，南北端墻各1,支。多點位移計的鉆孔及安裝施工安排在第廠 房三層開挖支護完成后，利用鉆爆臺車

58、進行施工，鉆機由16t吊車吊至鉆爆臺車 上，因此第四層開挖將延后48天。施工工期安排為2013年3月26日2013年 5月12日。C、高程1168.3m高程1169.30m邊墻多點位移計的施工高程1168.3m及1169.30m邊墻多點位移計共有6支，多點位移計的鉆孔及 安裝施工安排在第廠房四層開挖支護完成后，利用鉆爆臺車進行施工，鉆機由 16t吊車吊至鉆爆臺車上，因此第五層開挖將延后36天。施工工期安排為2013 年6月27日2013年8月1日。D、高程1165.3m南端墻多點位移計的施工高程1165.3m南端墻多點位移計共1支，多點位移計的鉆孔及安裝施工安排 在第廠房五層開挖支護完成后，利

59、用鉆爆臺車進行施工，鉆機由16t吊車吊至鉆 爆臺車上。多點為一件安裝施工可以與廠房第六層開挖同時進行。施工工期安排 為2013年9月16日2013年9月21日。E、廠房開挖及多點位移計安裝進度計劃安排廠房開挖及多點位移計安裝進度計劃安排（圖2）Programe of Powerhouse Excavation and Installation of Extensometer多點位移計安裝No.DescriptionDurationst art in g tunecompleti on time0,41118b l2O lloZOO240：2：80：3：20222012. 112012. 122

60、013. 12013. 22013. 32013.42013. 52013.62013. 72013. 82013. 913.91729 3111927412202$513211317252101826 M1220285 13213715233181624131?253111Concrete works for Crane Beam602012-11-022012-12-31- 2Extensometer inst allation above el evat ion 1176.30 m552012-12-162013-02-08 -3Third bench excavati on of th